Concentrator



May 10, 1927.

|-:. H. JOHNSON ET AL CONCENTRATOR Filed Oct. 21, 1925 Patented May 10, 1927.

UNITED STATES- PATENT OFFICE;

EDWARD HENRY JOHNSON AND ARTHUR HENRY WINTERTON, OF EAST RAND, TRANSVAAL, SOUTH AFRICA.

CON CENTRAT R.

Application filed October 21, 1925, Serial No. 63,913, and in the Union of South Africa October 22,1924.

The purpose of the present invention is to provide apparatus adapted to withdraw concentrate continuously from a stream of ore pulp which does not require skilled attention, and which may thus advantageously be substituted for the present amalgamating or concentrating tables.

The invention provides a drum arranged with its axis horizontal or somewhat inclined, the pulp stream being caused to flow through the lower part of the drum. The interior surface of the drum is of a suitable character to retain concentrate deposited from the pulp. The drum is slowly revolved so asto withdraw the deposited concentrate from the pulp and carry the same up the ascending side of the drum, whence it 1s suitably collected.

A perspective View with parts broken away, of one form of apparatus according to the invention is illustrated in Fig. I of the accompanying ClI'ZtWll'lgS; Fig. II shows a detail of one form of concentrating surface. 7

2 indicates the drum into which the pulp to be treated is fed by such means as the distributing launder 3. The treated pulp is discharged from the end 4 of the drum into a launder or the like 5. The drum is so set that the pulp flows through it at the desired rate, an inclination of six degrees at its lower surface having been found suitable for the treatment of tube mill effluent. The concentrate adheres to the surface of the drum and is carried up the rising. side of the drum (indicated by the arrow A) away from the pulp, being preferably washed by liquid distributed from the perforated pipe 7.

For collecting the concentrate there is shown a hopper 8 which extends for the length of the drum and has an open mouth or top 9 into which the concentrate is received. The concentrate is, when necessary detached from the drum surface by any appropriate means such as jets of water directed from a perforated pipe 10 onto the drum surface over the hopper mouth.

Provision may be made for adjusting the position of the hopper mouth about the surface of the drum, to bring it to the position at which the concentrate is most readily or conveniently displaced from the drum surface. For this purpose the hopper is provided with trunnions 11 co-axial with the drum and mounted in end frames 12.

flow off into a launder 15.

Rotation of the drum is effected by any suitable means such as a belt l6 passed aboutit. The rotational speed is adjusted to the rate at which it is desired to withdraw concentrate from the pulp stream; a speed of live revolutions per minute having been foundsuitable for tube mill efiluent pulp.

The interior surface of the drum is such as to retain the concentrate against the flow of the pulp stream and also to elevate it. In some cases there is used a surface'material such as grease. to which the concentrate adheres more readily than does the gangue material. In other cases the retention of the concentrate is due to the mechanical formation of the surface. The drawings show a rittled surface specially adapted for the purbosc of the invention. The riftles 17 are disposed at an angle so that to a substantial extent they oppose both the tendency for longitudinal movement dueto the scour and the slipping movement, at right angles to it, due to gravity. Their angular disposition is preferably such that they rise from the intake end of the drum on thereof.

This form of surface has been found suitable for n'ietalliferous concentrates. It may conveniently be formed on a rubber sheet 18, a portion of which is shown to an enlarged scale in Fig. II. Said sheet may be fixed to the wooden lining 19 of the drum.

lVe claim In a concentrator, the combination of a rotatable drum, means to rotate thesame in one direction. means to pass material to be treated into the drum at one end, the material being discharged from the other end of the drum, the internal surface of the drum having riftles inclined inwardly and upwardly from the intake end of the drum on the rising side thereof, and means to collect concentrate from the surface of the drum.

In testimony whereof we affix our signatures.

EDWARD HENRY JOHNSON. ARTHUR HENRY wmrnnrou.

the rising side 

